Recently, the printed image typified by photographic image and poster is formed by an ink-jet apparatus or an electrophotographic image forming apparatus additionally to usual silver halide photographic system and gravure printing method.
For instance, formation of an fine dot image on a level of 1,200 dpi (dpi: dot number per inch (2.54 cm)) is made possible in the field of the image forming technology of electrophotography such as copying machine or printer accompanied with the progress in the technology such as digitalization of exposing system and minimizing of the toner diameter. Moreover, a technology capable of forming a full color image is developed in which toner images are respectively formed on plural photoreceptor drums and the formed toner images are piled by primarily transferred onto an intermediate transferring member, and the image formed on the intermediate transferring member is secondarily transferred onto image support material. As above-mentioned, the formation of full color image requiring high resolving power such as that of the photographic image can be realized by such the image forming method additionally to the usual silver halide photography or printing technology.
A glossy image is often required in a photographic image of poster; however, white background area with low glossiness of the image formed by the toner is obtained sometimes even though the images area fixed on the support such as a paper sheet has some degree of glossiness. Such the unbalance in the glossiness in the finished image causes degradation in the image quality of the printed matter; therefore countermeasure to such the phenomenon is demanded.
On such the background, a technique is investigated, by which the image formation is carried out by using a toner constituted by omitting colorant from the usual color toner, so called as a transparent toner or clear toner, for preventing the formation of irregularity in the glossiness on the image. In concrete, a technique is disclosed, in which the transparent toner is uniformly provided on the whole surface of the support carrying the image and heated and cooled to form a transparent toner layer on the whole surface of the image for preparing a printed matter having uniform glossiness on the whole surface of the image; cf. Patent Document 41, for example.
Furthermore, a full color image forming technique is known, in which difference of the physical properties between the image forming toner and the transparent toner is noted and the difference between the particle diameter of the colored toner and that of the transparent toner is specified to obtaining the uniform glossiness; cf. Patent Document 4, for example.
Moreover, a technique is disclosed in which a transparent toner layer is formed on the image formed by a printer by using a glossing apparatus to provide a glossy printed matter. Such the apparatus is connected with a printer such as an electrophotographic printer and the transparent toner layer is entirely formed on the surface of the image formed by the printer, and the transparent toner layer is melted by heating the layer in a state of contacting with a belt. And then the transparent toner layer is solidified by cooling while contacting with the belt. The printed matter is naturally released from the belt after solidifying of the transparent toner layer; thus the printed matter having uniform glossy surface is finished; cf. Patent Documents 2 and 3, for example.
While the uniform glossy surface formed on the image is effective to give additive value, it sometimes damages the image of beauty by sticking finger prints on the image surface when naked hand touches the finished prints. For example, finger prints on the black area are remarkable when a monochrome image poster having higher density is prepared, and the stick finger prints affect commercial value. Therefore it is required to handle the printed matter not to give finger prints in the working place of print material, and countermeasure to avoid sticking fingerprints by the operators is applied to the utmost. Practically, the operators have thin gloves fitting closely to their hands to handle the print matters. However, there are problems that when operation is conducted always having gloves, hands become sultry by sweat and the print matters are stained by the stained gloves, and further the operator, who cannot stand the heat, touches carelessly without having gloves and stick finger prints.
Investigation has been conducted to avoid sticking finger prints on the product in various area in addition to the print matters in view of above described background. The counter measure techniques to avoid sticking finger prints include, for example, one applying coating composition of anti-finger print composition containing acrylic resin stipulating hydroxy value or UV ray curable type over print varnish composition containing specific compound; cf. Patent Documents 5 and 6, for example.